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The Mandukya Upanishad
Swami Krishnananda's in-depth coverage of the Mandukya Upanishad. Click on the Publishers' Preface to see what each section offers.
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Swami Krishnananda: Essays on the Upanishads
Swami Krishnananda's essays on the Isavasyopanishad, the Kenopanishad, and the Kathopanishad.
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Upanishads: Treasure of Wisdom
Sri Swami Sivananda summarizes the "origin" and "significance" of the ancient Upanishad texts.